1. Field of the Invention
The present invention generally relates to energy absorbing systems and, in particular, to an energy absorbing component of such systems. Energy absorbing systems, of the kind to which the invention relates, are utilized in various automotive vehicle applications to absorb forces during an impact and to enhance the collision protection of the vehicle's occupants.
2. Description of Related Art
In numerous applications, it is desirable to provide a means by which the shock or impact forces of a collision are absorbed. This is particularly true in automotive vehicles, where the side of the vehicle is often subjected to impact. Side impacts may occur anywhere along the side of the vehicle, but when they occur in the door regions, they may particularly result in the forces of the impact being transferred through the door regions into the passenger compartment or cabin of the vehicle. For this reason, many original equipment manufacturers include energy absorbing components (also known as energy absorbers), of one type or another, between exterior and interior panels, or other structures, of the vehicle doors.
Various types of energy absorbing components are known. Typically, these energy absorbing components operate by being positioned between two elements of the vehicle, such as a sheet metal panel and then interior trim panel of a door, and deforming under stress. The energy absorbing components may take many forms, including foam blocks of suitable density and rigidity. Suitable foam blocks, because of the required density, can significantly add to the weight of the door and, ultimately, the vehicle, particularly when the distance between the two elements is large.
In such instances, hollow elongated bodies have found use as the energy absorbing components. These hollow bodies are generally made of plastic and have a variety of shapes including rectangular, cylindrical or conical. During use, a force applied exteriorly to the door is transferred to one end of the hollow body. The hollow body is designed so that when the body experiences a given stress, it will either elastically or plastically deform, thereby absorbing some of the force being exerted against the door and reducing the amount of force that is transmitted through the door and potentially to an occupant of the vehicle.
When undergoing deformation, the hollow body may be designed to react in a variety of ways. In one known reaction manner, while the hollow body is crushed, it collapses upon itself. Controlling such a collapse is an important consideration in the design of an energy absorbing component of this variety.